Trimming mechanism for sewing-machines.



J. BERGER, In. TRIMMING MECHANISM FOR SEWING MACHINES. APPLICATION FILED JuLY2o 19w.

2 SHEETS-SHEET 1 PatentedAug. 6,1918.

J. BERGER, In. TRIMMING MECHANISM FOR SEWING MACHINES.

- APPLICATION FILED JULY 20 l9l5. 1,274,666. Patented Aug. 6, 1918.

2 SHEETS-SHEET 2- UNITED STATES PATENT OFFICE;

JOSEPH BERGER, JR., U'IICA, NEW YORK, ASSIGNOR 'IO UNION SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

TRIMMING' MECHANISM FOR SEWING-MACHINES.

Specification of Letters Patent.

Patented Aug. 6, 1918.

Application filed "July 20, 1915. Serial No. 40,893.

To all whom. it may concern:

' Be it known that I, Josnrir BlillGlClt,-Jl.,

a citizen of the United States, residing at An ob'ec-t of the invention to provide a trimming mechanism of the above character, wherein the stationary member is carried by the presser foot and the movable member is supported by a yoke carried by the presser bar, said yoke, being movable about the axis of the bar for trimming and I endwise of the bar for holding the trimming members in contact.

'A further object of the invention is to provide a trimming mechanism of the above character, wherein the oscillating yoke has a two point support from the presscr bar,

one above the lowerbearing for the pressure bar and the other below the same.

A still further object of the invention is to provide a trimming mechanism 'of the above character, wherein the movable trimming member is supported by an oscillating yoke and the stationary trimming member is carried by the presser foot and said trimming members have relative movement in a. substantially horizontal plane with supporting means for the presser foot in addition to the presser bar, so that the stationary trimming member is rigidly held from movement due to the force thereagainst incident to'the cutting operation.

In the drawings which show by way of illustration one embodiment of the inven tion,-

Figure 1 is a View partly in front elevation and partly in section, showing a sewing machine having my trimming mechanism applied thereto;

Fig. 2 is a view partly in section and partly in plan, showing on an enlarged scale the supporting yoke for the movable trimming member, the presser foot, the stationary member and the end of the work support;

Fig. 3 is an enlarged vertical sectional view through the supporting yoke and presser foot;

Fig. -l is a view in front elevation showing the presser foot, the trimmer, the needles, and the strip guide turned to inoperative position, the work support being shown in dotted lines;

Fig. 5 is a dctial in plan, showing the supporting yoke; the means for oscillating the same and the movable trimmer carried thereby;

' Fig. 6 is a detail showing the relative positions of the trimming members. the prcsser foot and the edges of the fabric sections being trimmed; and

Fig. 7 is a detail showing diagrammatically the flat scam formed on my machine.

In Fig. 1 of the drawings, I have shown a sewing machine consisting of a supporting base 1, which carries a standard 2, on which is mounted an overhanging arm 3. At the outer end of the overhanging arm is a supporting head 4, in which reciprocates a needle bar carrying needles 66 and 77. The needle bar is reciprocatcd-by a needle lever S, which is secured to the needle bar by a link 9. The needle lever 8 is oscillated by an eccentric strap 10 which cooperates with an eccentric on the main shaft 11. -EX- openings 15 and 16 for the pairs of needles 6-6 and 77, respectively. Said presser foot is also provided with a seat for the stationary member 17 of the trimmingmeehanism. Said stationary member is held in its seat by a clampi'ngplate 18.and a clamping screw 19 which passes through the plate into the presser foot. Said presse'r foot is also formed with a guiding channel 20. This guiding'channel extends back into the foot substantially to the rear edge of the stationary trimming member 17. Cooperating with this stationary trimming member 17 is a movable trimming member 21, which is clamped to an arm '22 by a clamping screw 2?). which yoke is mounted on the presser bar 14. The upper bearing 25 of the yoke is above the lower bearing 4 of the supporting head 4 and the lower bearingQG is also carried by the presser bar 14 at a point below the lower bearing 4 for the supporting head 4 and also at a point directly above the shank of the presser foot 13. The bearing 26 extends downwardly to form a support 27 for the arm 22, sald arm being split so as to be clamped against the said support by a clamping screw 28. This voke is free to oscillate on the presser bar 14 and is forced downwardly along the bar by a spring 29, which, at its lower end engages the upper bearing 25 of the yoke and at its upper end engages a collar 30. This collar 30 clamped to the presser bar by a set screw 31. A limiting collar 32 is also secured to the presser bar by a set screw 33. This collar engages the lower face of the upper bearing :25 of the yoke and takes a part of the strain off of the trnnmer blade 21. The spring 29, however, holds the trunming blades in shearing relationto each other. The blade 21 is formed with a finger 34 which normally projects over the stationary trimming blade or member .17, so that the blade or member 21 makes continuous contact with the blade 17.

The yoke 24 has an arm 35 whlch projects forwardly from the yoke and a link 36 is connected to a ball stud carried by this arm. The link 36 is pivoted to a rock arm 87 at its rear end and this rock arm is pivoted at 38 to a suitable lug 39 on the standard 2. The rock arm at its other end is connected to a link 39 which in turn is pivoted to a ball stud 40 on the needle lever 8. As the needle lever oscillates the yoke will be oscillated back and forth and thus operate the movable trimming member.

A strip guide Or deflector 41 is secured to an arm 42 which is pivoted at 43, see Fig. 3, to the shank of the presser foot. This strip guide extends laterally across the channel 20 and serves to deflect the trimmed off edge of the material away from the stitch forming mechanism. As clearly shown in Fig. 4, there is a fixed auxiliary section 44, which is in line with the strip guide when in normal position and the strip guide has a cut away space 45 for this auxiliary section 44. This permits the strip guide 41 to be swung freely over the top of the clamping plate and the clamping screw for the stationary trimming member when access to the needles is desired.

As clearly shown in Fig. 6. two sections of fabric a and b which are to be united are the trimming mechanism.

The arm :22 is supported by a yoke 24,

directed through the guiding channel 20 to The upturned edges are trimmed by the movable trimming blade cooperating with the stationary blade of the trimming mechanism. After these edges are trimmed they pass underneath the presser foot and the edges are abutted, as shown in Fig. 7, where they are joined and covered by the stitches 0 and (Z. The stitches c are formed by the needles G6, together with their complemental stitching mechanism; while the stitches (l are formed by the needles 77 and their complemental stitching mechanism.

The presser foot 13 has an arm 46 projecting rearwardly therefrom and this arm is forked so as to engage a presser guide bar 47 carried by the supporting head 4. This arm 46 serves to prevent the presser foot from turning on the presser bar 14 or the presser bar 14 from turning in its bearings .due to the force of the mo able trimming blade against the stationary trimming blade during the normal trimming action.

From the above, it will be apparent that I have provided a trimming mechanism wherein the stationary blade is carried by the presser foot, so that it moves up and down as the thickness of the material varies, and the movable blade is held in yielding contact with this stationary blade, and is also moved up and down with the presser foot. This trimming mechanism is positively actuated and is located in advance of the stitchin mechanism, so that the trimmed edges may be covered to form a flat seam.

It is obvious that minor changes in the details of construction may be made without departing from the spirit of the invention as set forth in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A trimming mechanism for sewing machines comprising a stationary member, amovable member cooperating therewith, a yoke, means for oscillating said yoke about a vertical axis, said yoke having an extended bearing projecting downwardly from its lower end, and an arm clamped to said hearing for supporting said movable trimming member.

2. A trimming mechanism for sewing machines comprising a stationary member, a movable member cooperating therewith, a yoke, means for oscillating said yoke about a vertical axis, said yoke having an extended bearing projecting downwardly from its lower end, an arm clamped to said bearing for supporting said movable trimming member. and a spring for yieldingly forcing said yoke downwardly for yieldingly holding said movable member in contact with said stationary member.

3. A trimming mechanism for sewing ma.-

chines comprising a horizontal stationary member, a horizontal movable "member comember toward the stationary member, and

an adjustable member for limiting the thrust of the movable member toward the stationary member.

4. A trimming mechanism for sewing machines comprising a horizontal stationary member, a horizontal movable member cooperating therewith, a yoke, a supporting rod on which said yoke is pivotally mounted so as to turn about a vertical axis, means for oscillating the yoke, an arm carried by the yoke on which said movable trimming member is mounted, and an adjustable collar on the rod for holding the yoke in a predetermined position on the rod.-

5. The combination of a presser foot, a presser bar supporting said foot, a stationary trimming member carried by the presser foot, a movable trimming member cooperating witlrsaid stationary member, a yoke mounted on said presser bar, means for oscil lating said yoke about said presser bar, an arm carried at the lower end of said yoke for supporting said movable trimming member, a spring on the presser bar engaging the yoke and forcing the same downwardly so as to yieldingly hold the movable trimming member in contact with the stationary trimming member, and an adjustable member on the presser bar for limiting the thrust of the movable trimming member toward the stationary trimming member.

6. The combination of a presser foot, a presser bar supporting said foot, a stationary trimming member carried by the presser foot, a movable trimming member cooperating with said stationary member, a yoke mounted on said presser bar, the lower bearing of said yoke being below the supporting head for the presser bar and adjacent the shank of the presser foot, and an armcarried by the yoke for supporting said movable trimming member.

7. The combination "of a presser foot, a presser bar supporting said foot, a stationary trimming member carried by the presser foot, a movable trimming member cooperating with said stationary member, a yoke carried by the presser bar, the lower bearing of the yoke being below the lower bearing of the support for the presser bar and adjacent the shank of the presser foot, the lower bearing of said yoke being extended downwardly, and an arm clamped to said bearing and carrying said movable trimming member.

8. The combination of a presser foot, a presser bar supporting said foot, a stationary trimming member carried by the presser foot,

a movable trimming member cooperating with said stationary member, a yoke carried by the presser bar, the lower bearing of the yoke being below the lower bearing of the support for the presser bar and adjacent the shank of the presser foot, the lower bearing of said yoke being extended downwardly, an arm clamped to said bearing and carrying said movable trimming member, a spring surrounding the presser bar and engaging the upper bearing of the yoke, and a collar fixed to the presser bar for placing said spring under tension,

9. The combination of a presser foot, a presser bar supporting the same, a stationary trimming member mounted on said presser foot and disposed horizontally, said presser foot having a fabric guiding channel terminating in rear of said stationary trimming member, a horizontally movable trimming member cooperating with. said stationary trimming member,, a yoke mounted on said presser bar, means for oscillating the yoke about the longitudinal axis of said presser bar, an arm rigid with said yoke and carrying'said movable trimming member, a spring carried by the presser bar and engaging the upper end of said yoke, a collar fixed to the presser bar for maintaining said spring under tension, and a second collar fixed to the presser bar against which the yoke bears for limiting the thrust of the movable trimming member against the stationary trim ming member. I

In testimony whereof, I aflix my signature, in the presence of two witnesses.

JOSEPH BERGER, JR.

WVitnesses I L. D. MoCoRMAo, EARL C. CLARK. 

